Novel Ag2S quantum dot modified 3D flower-like SnS2 composites for photocatalytic and photoelectrochemical applications
Novel Ag2S quantum dot modified 3D flower-like SnS2 composites for photocatalytic and photoelectrochemical applications
复制标题
用于光催化和光电化学应用的新型 Ag2S 量子点改性 3D 花状 SnS2 复合材料
DOI：
10.1039/c7qi00513j
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发表时间：
2017
影响因子：
7
通讯作者：
Li Huaming
中科院分区：
文献类型：
--
作者：
Jing Liquan;Xu Yuanguo;Zhang Meng;Xie Meng;Xu Hui;He Minqiang;Liu Jie;Huang Shuquan;Li Huaming
采用水热-离子交换法制备了Ag 2S/SnS 2三维花状复合材料。均匀的Ag 2S量子点均匀地散布在3D花状SnS 2上。通过X射线衍射（XRD）、拉曼光谱、扫描电子显微镜（SEM）、能谱（EDS）、透射电子显微镜（TEM）、紫外-可见漫反射光谱（DRS）、X射线光电子能谱（XPS）和光致发光（PL）等测试手段对样品进行了表征。结果表明，Ag 2S量子点修饰的三维花状SnS 2复合材料具有较好的光电化学性能和光催化活性。3%的3D花状Ag 2S/SnS 2在2.0V（vs. Ag/AgCl）（0.65mA cm-2）下的光电流密度是3D花状SnS 2的光电流密度（0.2mA cm-2）的约3.25倍。通过可见光下橙子的降解和光催化放氢性能评价了三维花状Ag 2S/SnS 2复合材料的光催化活性。SnS 2和Ag 2S量子点的耦合可以显著提高光催化活性。实验结果表明，3%3D花状Ag 2S/SnS 2复合材料对橙子的光催化降解效果最好。这些复合材料在可见光照射下也表现出574.7 μmol h−1 g−1的高H2释放速率，比纯3D花状SnS 2高约5.57倍。根据计算、自由基捕获实验和ESR，提出了一种可能的光活性增强机理。这项工作提供了实验洞察设计的低成本的光催化剂，高效的光降解和光催化H2-生产。
Novel 3D flower-like Ag2S/SnS2 composites were fabricated by a hydrothermal and ion exchange method. Uniform Ag2S quantum dots were homogeneously interspersed on 3D flower-like SnS2. The samples were characterized through X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) analysis. As expected, the as-prepared Ag2S quantum dot modified 3D flower-like SnS2 composites exhibited enhanced photoelectrochemical (PEC) performance and photocatalytic activities. The photocurrent density of 3% 3D flower-like Ag2S/SnS2 at 2.0 V (vs. Ag/AgCl) (0.65 mA cm−2) was about 3.25 times higher than that (0.2 mA cm−2) of 3D flower-like SnS2. The photocatalytic activity of 3D flower-like Ag2S/SnS2 composites was assessed through the degradation of methyl orange and the photocatalytic H2 evolution performance under visible light irradiation. The coupling of SnS2 and Ag2S quantum dots could notably promote the photocatalytic activity. The experimental results indicated that 3% 3D flower-like Ag2S/SnS2 composites showed the best photocatalytic performance for the degradation of methyl orange. These composites also exhibited a high H2 evolution rate of 574.7 μmol h−1 g−1 under visible light irradiation, approximately 5.57 times higher than that of pure 3D flower-like SnS2. Based on the calculation, radical trapping tests and ESR, a plausible mechanism for increased photoactivity was proposed. This work provides experimental insight into the design of low-cost photocatalysts for highly efficient photodegradation and photocatalytic H2-production.